Various article transport facilities that use rail-guided article transport vehicles are in practical use. In article transport facilities with a rail, dust is generated as a result of the rail and wheels of article transport vehicles coming into contact with each other, and may make the article transport facilities dusty. Regular manual cleaning of dusty article transport facilities takes time and effort. JP 2001-128303A discloses an article transport facility that has a function of removing such dust (hereinafter, reference numerals in parentheses in BACKGROUND ART denote corresponding components in the referenced document). In this article transport facility, a truck (12) travels along a rail (2) having a U-shaped cross section in a state in which a travel wheel (25) of the truck (12) is in contact with the bottom of the rail (2), and guide rollers (26) are in contact with the inner surface of the U-shaped rail (2). Holes are formed in the bottom of the rail (2), and a filter fan unit (10) is provided on the outer side of the bottom of the rail (2). The filter fan unit (10) sucks air from the holes formed in the bottom to remove dust generated as a result of the truck (12) traveling (see, for example, FIG. 1 and paragraph [0011] of JP 2001-128303A)
In such a case where an article transport vehicle travels on the bottom of a U-shaped rail that serves as a travel surface, dust generated due to travel accumulates inside the rail, and thus it is possible to suck out the dust via the holes provided in the bottom. However, there is also a type of article transport facility in which an article transport vehicle travels on the upper surface of a rail that serves as a travel surface. In this case, dust generated due to travel does not accumulate in a relatively closed space (space that is enclosed in its periphery while being partially open, such as the inside of a U-shaped rail), and thus it is more difficult to automatically collect the dust. Accordingly, it is desirable to appropriately remove dust that is generated as a result of an article transport vehicle traveling, even if a travel surface is provided in an open space.